Separable fastener



Mrch 21, 1933. s N RTO 1,902,416

SEPARABLE FASTENER- Filed Aug. 4. 1930 29 5: INVENTOR.

SamueZH/V0 rion. BY

ATTORNEY Patented Mar. 21, A

sexual. H. nonron, or minus, rnimsyrivama' "Assretr'on 'ro noox Ess 'rasrnmzaconm, A. coRronArIoN-or PENNSYLVANIA? snrananan rasram Application fled mm 4, laao.v Serial No. 472,846.

My invention relates to separable fasteners and 1s particularly applicable to that class of fasteners which has come to be known as slide fasteners.

5 In the manufacture of the metal elements of A slide fasteners either one of two processes is ordinarily followed. One process consists of forming the interlocking socket and .head and punching the members from a flat strip of metal leavin a considerable portion of scrap.

Another metiod is to roll a wire to a general- 1 Y-shape cross-section and slice ofi elements rom the cross-section or end of the wire. In either case it will be observed that the inhercut nature of the manufacturing process is such as to leave at least some edges of the elements burred and relatively sharp. Also it is evident that the majority of the corners will be right angle corners. This cannot be f avoided in large production especially when it is considered that these elements must be made of non-rustable metal such as what is commonly lmown as nickel-silver. Various bufling and smoothing processes have been tried out with more orless success, to take off the burred edges and thus makinithe fastener smooth enough to be accepta le' for use. .The difliculty of this problem is increased a due to the fact that in the machines ordinarily used for making fasteners, theielements are cutand formed and then attached directly to the tape without letting go of themiand thus they cannot ordinarily be tumbled in bulk after they are formed. 85

, fact that the application ofa suitable coating of lacquer or paint to'metal surfaces in gen-- eral will smooth out' the very small cracks and minature holes insuch surfaces, but with my invention I believe that special and novel results are. secured which would not be exected, without considerable experiment, to gollow the mere application of a coat of paint to the fastener as any other article is painted.

- In a small articleof this nature when applied tosuch things as ladies handbags and clothing, it ishighly desirable that the metal elements present a smooth exterior, since the sharp I 5 elements will scratch the hand where. it comes I am, of course, aware ofthe well-known 4 edges ordinarily formed on the metal in contact with the elements. So far as I am' aware although this objectionable feature has been observed for many years since the slide fastener has come into wide use, no one. has ever demonstrated the effectiveness of a proper application of lacquer, or the like, to the metalelements in 'smoothingjup the entire fastener and'jalsomaking a much more smoothly operated article.

One of the objects of my invention is to produce an improved fastener construction in which the relatively sharp exterior edges normally on the metal fastener elements areeliminated, to produce a much smoother fas- I tener.

Another object of my invention is' to provide an improved fastener .construction of the above typein which a coating of lacquer or the like is applied to the exterior surfaces of the elements to round out the relatively sharp exterior edges normally present on such elements and at the same time, to providea durable and decorative finish for said elements. 1

Another object of my invention is to provide an improved construction of slide fastener in which the fabric stringers are suitably stiffened between the fastener elements.

Other objects and advantages of the invention will hereinafter more fully appear.

Inthe f accompanying drawing, I have shown for purposes of Illustration, one embodiment which my invention may assume in practice. In the drawing: 4

Fig. 1 is a plan view of the slide fastener to which my invention isapplicable.

2 is a longitudinal section through one of the fastener stringers illustrating my invention embodied therein.

Fig. 3 is an isometric view of a metal fastener element in normal condition with the roughness of the edges slightly exaggerated.

Fig. 4 is a transverse sectional view through one of the fastener stringers showing my invention associated therewith.

- ig. 5 shows a portion of a fastener while being closed under strain. I The fastener with which I have "illustrated my invention for purposes of exemplificati'on, has a pair of flexible fastener stringers 6 and 7 each of which comprises a fabric tape havthis type of'fasten'erreference is made to the patent to Gideon March 20, 1917. It is suflieient here to say that each of the fastener elements 10 has an 111-- terlocking end formed with a projection 11 and a socket 12, which sockets and projections interlock with those of adjacent elements to hold the fastener @ether. These elements are progressively mgr: or disengaged by movement of a slider 3, which may be actuated by an attached pull member 14. A suitable bottom stop and, stringer connecting member 15 is arranged at the lower end of the sries of elements and a pair of top sto elements 16 are attached to the stringers a jacent the other ends of the series of elements. Each of the .fastener elements as well as the stop elements, have clamping jaws for engaging over the corded edges 8 and 9 such clamping jaws being best indicated in Figs. 3 and 4 by the numeral 17. I

Referring now to Fig. 3, it will be observed that the long edges or right angle corners 18 of the fastener elements 10 are more or less sharp and burred and this is especially true when the fastener is manufactured by means of the stamping out process above described. It will also be observed that these long outside faces of the fastener element have tool marks 19 formed therein caused by the side clampingtools in pinching the jaws 17 on the corded edges 8 and 9 of the tape. At the jaw end of the fastener elements, there will also be observed sharp or right angle corners 20 and 21 and it is the edges 21 which are particularly objectionable when they are sharp or burred. This edge 21 forms the exterior corner of the fastener and comes in contact with the hand of the user more frequently than other edges. Also the front edge 22 near the interlocking socket 12 is normally left sharp or rough which is objectionable in articles like handbags'where the hand must be inserted into the bag between the fastener elements while the fastener is I have found that all of these sharp edges are eliminated to a surprising degree and also the o eration of the slider is rendered smoother by the application of a relatively heavy coating 23 of lacquer or the like, to all of the exterior surfaces of the fastener element after they are clamped to the fabric stringers. It is desirable to have the lacquer or other coating applied in sufiicient quantity to smooth out all sharp edges and give the corners a rounded effect. As illustrated in Fig. 2, the normally sharp edges or corners undback No. 1,219,881,

18 are formed into roundededg'es or corners 24 and the edges 21 are formed into rounded corners 25 as seen in Fig. 4. It will also be ,clear that the tool marksare eliminated and any unevenness in the surfaces of the elements is obliterated.

Referring to Fig. 5 it will be observed that when the slider is being pulled up with the fastener under strain, the corner 26 of the slider will have a tendency to catch behind the jaw end of one of the fastener elements 10. This tendency for the slider to catch and hinder the closing movement depends upon the flexibility of the fastener stringer to a certain extent. With the stringer formed as in the usual mannerby means of a flat fabric locking end of the fastener will contribute v to the smooth operation of the fastener.

Various coatings may be found suitable for the purposes of my invention and preferably a suitable lacquer is sprayed on the fastener elements and adjacent portions of the tape and simply allowed to dry in the atmosphere. In order to make the coating more durable, however, to resist the wear of the slider, it may be baked on at a temperature which will not injure the fabric of the tape. It will be evident that for decorative purposes the entire tape as well as the slider andstop elements maybe covered with the lacquer if desired and that the color may be varied to suit the requirements.

While I have in this application specifically described one mode of carrying my invention into effect and suggested some departures therefrom, it will be understood that the foregoing description and drawing are merely for the purposes of explanation and various other forms will occur to those skilled in the art.

What I claim as my invention is:

1. In a separable fastener, a pair of fas tener stringers, a series'of metal fastener elements attached to each of said stringers for fastening said stringers together, some of said metal elements having right angle corners, and a coating applied to all of} e exterior surfaces of each individual element to make said corners rounded and produce a smooth fastener.

2. In a slide fastener, a pair of flexible stringers, cooperating series of metal fastener elements on adjacent edges of said stringers, a slider movable along said elements to engage and disengage the same, each of said elements normally having certain of its edges relatively sharp or burred, and as coating of lacquer sprayed on all of the exterior surfaces of each individual element which are disposed on at'least one side of said stringers to round saidsharp or burred edges to produce a smooth fastener.

3. In a slidejfastener, a pair of fastener stringers, cooperating series of metal fastener elements attached to the adjacent edges of said stringers, a slider movable along said elements for engaging and disengaging same, each of said elements having an lnterlocking 1 head at one end and clamping jaws at the 7 other end, the exterior edges at the jaw ends of said elements being normally sharp or buried, and a'separate and individual coating of lacquer applied to the exterior surfaces of each individual element adjacent said corners to eliminate said sharp edges and thereby provide for smoother operation of said slider.. g e

4. In a slide fastener, a pair of fabric stringers, cooperating series of fastener ele-' ments closely spaced along the adjacent-edges of said stringers, a slider movable along said elements for progressively engaging or releasing the same, said elements being of a generally block-like shape and having right angle corners with normally sharp exterior edges, and a coating-of lacquer sprayed on. each individual element in sufiicient quantity to smooth out said edges and make the corners slightly rounded, saidcoating completely covering each element.

5. In a slide fastener, apair of fabric stringers, cooperating series of fastener elements closely-spaced along the adj acent edges of said stringers, a slider movable along said elements for progressively engaging or releasing the same, said elements being of a. generally block-like shape and having right angle corners with normally sharp exterior edges, and a coating of lacquer sprayed on each individual element in suflicient quantity to smooth out-said edges and make the corners slightly rounded, said coating of. lacquer completely covering each element and extending also over said fabric stringers.

In testimony whereof I aflix my signature. 9

SAMUEL H. NORTON. 

